I don't think it's possible to get "very loud": very loud speakers have cones that make it possible to transfer large amounts of energy to the air. By comparison, HD head assemblies are downright "aerodynamic". Not much surface area to create air pressure.

If all you want is clicking or buzzing, something like an L293D H-bridge is a fairly cheap way to drive the voice coil with square waves.

Or this guy might give you more oomph than an LM386 for driving it with an analog signal.

I've ordered the chips already, but not placed the other for the caps and all the rest yet.

I also tested a straight 9v battery across the pins and it worked too. It slammed the head all the way one way (and I would presume it would slam it the other way if I sent it -9v).

I've not used an H-bridge before. What I want to do is get the voice coil to bounce around (hard), so it makes an audible clacking/clicking. Using the audio amp as a driver seemed to have the cool side effect of actually amplifying (acoustically) the squarewaves I was sending it, so you would hear the squarewaves as the head moved around on the platter, and if it was loud enough, that would move the head around enough to hit the end posts, which would then make an even louder click.

Get an old scrap hard drive that barely works except for the motor or has almost no memory. It would be a shame to waste a good hard drive on a device to annoy your little brother or sister or parents. You may be better off just using some motors with a clicker of some type hooked onto them. Maybe a dog training clicker would be a cool noisemaker.

Technician at Yuneec Electric Aviation

mowcius

Get an old scrap hard drive that barely works except for the motor or has almost no memory. It would be a shame to waste a good hard drive on a device to annoy your little brother or sister or parents.

Have you even read the rest of the post?

You also obviously have no idea how many scrap hard drives we all have lying around - I can see at least 10 from here. Some are broken, some are just less than 40GB or so and about 10 years old - I'm not going to trust my data on one of them...

motorhead

Hi Krissta, great thread! I'm trying to do the same thing I think. I want to click the head back and forth really fast to play a tune.

After reading through this thread and various others I've confused my self a bit. Can you or anyone confirm if I am on the right lines?

I have been looking at the H-bridge SN754410 because I can get hold of them pretty cheaply and easily. Is this the kind of bridge I would need to control a VCM in a hard disk? Also look back to the picture you posted of lots of disks, does this only work with certain types of hard drive or generally any that use a VCM?

I have the following hard drive (with the lid off: http://i55.tinypic.com/15d9xqw.jpg) and after turning the arm upside down I found these two pins, does that look like I'm barking up the right tree? (http://i52.tinypic.com/2vb0iyt.jpg)

Yeah I tested tons of different harddrives. The principal/approach worked with most of them. I believe it would work with all of them given you have access to the right pins. It's easier to get to on some. I also found that the 'above surface' kind sounded better, and were easier to work with. The one you have is kind of recessed in, which minimizes some of the sound of the platter/arm and makes it hard to get to the points.

I accessed my points where the ribbon meets the flat part, as if you solder right to those wires it will eventually break as it'd be moving all of the time.

I also used a straight up audio power amp to drive the VCM. So I'm going from the audio out of my computer into a home stereo, and the speaker out from that going into the HDs.

Hope that helps. And post any results you get!

opkach

Hello! I have recently started to look into the idea of using an Arduino to interface with an old hard drive spindle. I took apart an old 30GB Maxtor from an old mac tower but i've been having some issues. I looked through this thread, which was extremely informative but I was curious if anyone had a diagram of the schematic that was mentioned on the first page of this thread. Does anyone know of any good tutorial sites instead of just a video and a code example? I've been having a hard time with this and I its slowly getting to me that I can't figure it out. Any ideas?

Whoops, I was cleaning up my webpage, and I had forgotten I linked it up here. I'm away at a festival at the files are on my external HD back home, but I'll upload it as soon as I get back (start of the week).